#include <stdio.h>
#include <string.h>
#include <stdlib.h>

int main()
{
	char* user = getenv("USER");
	if(strcmp(user, "root") == 0)
    {
        printf("myself command!\n");
    }
    else
    {
        printf("%s是一个非法用户！\n", user);
    }
    
	return 0;
}
